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aya: Implement .kconfig support #1017

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2 changes: 1 addition & 1 deletion .github/workflows/ci.yml
Original file line number Diff line number Diff line change
@@ -299,7 +299,7 @@ jobs:
run: |
set -euxo pipefail
find test/.tmp -name '*.deb' -print0 | xargs -t -0 -I {} \
sh -c "dpkg --fsys-tarfile {} | tar -C test/.tmp --wildcards --extract '*vmlinuz*' --file -"
sh -c "dpkg --fsys-tarfile {} | tar -C test/.tmp --wildcards --extract '*vmlinuz*' --wildcards --extract '*config*' --file -"

- name: Run local integration tests
if: runner.os == 'Linux'
213 changes: 210 additions & 3 deletions aya-obj/src/btf/btf.rs
Original file line number Diff line number Diff line change
@@ -18,11 +18,12 @@ use crate::{
info::{FuncSecInfo, LineSecInfo},
relocation::Relocation,
Array, BtfEnum, BtfKind, BtfMember, BtfType, Const, Enum, FuncInfo, FuncLinkage, Int,
IntEncoding, LineInfo, Struct, Typedef, Union, VarLinkage,
IntEncoding, LineInfo, Struct, Typedef, Union, Var, VarLinkage,
},
generated::{btf_ext_header, btf_header},
generated::{bpf_map_type, btf_ext_header, btf_header, BPF_F_RDONLY_PROG},
maps::{bpf_map_def, LegacyMap},
util::{bytes_of, HashMap},
Object,
EbpfSectionKind, Map, Object,
};

pub(crate) const MAX_RESOLVE_DEPTH: u8 = 32;
@@ -157,6 +158,20 @@ pub enum BtfError {
/// unable to get symbol name
#[error("Unable to get symbol name")]
InvalidSymbolName,

/// external symbol is invalid
#[error("Invalid extern symbol `{symbol_name}`")]
InvalidExternalSymbol {
/// name of the symbol
symbol_name: String,
},

/// external symbol not found
#[error("Extern symbol not found `{symbol_name}`")]
ExternalSymbolNotFound {
/// name of the symbol
symbol_name: String,
},
}

/// Available BTF features
@@ -463,6 +478,57 @@ impl Btf {
})
}

pub(crate) fn type_align(&self, root_type_id: u32) -> Result<usize, BtfError> {
let mut type_id = root_type_id;
for _ in 0..MAX_RESOLVE_DEPTH {
let ty = self.types.type_by_id(type_id)?;
let size = match ty {
BtfType::Array(Array { array, .. }) => {
type_id = array.element_type;
continue;
}
BtfType::Struct(Struct { size, members, .. })
| BtfType::Union(Union { size, members, .. }) => {
let mut max_align = 1;

for m in members {
let align = self.type_align(m.btf_type)?;
max_align = usize::max(align, max_align);

if ty.member_bit_field_size(m).unwrap() == 0
|| m.offset % (8 * align as u32) != 0
{
return Ok(1);
}
}

if size % max_align as u32 != 0 {
return Ok(1);
}

return Ok(max_align);
}

other => {
if let Some(size) = other.size() {
u32::min(BtfType::ptr_size(), size)
} else if let Some(next) = other.btf_type() {
type_id = next;
continue;
} else {
return Err(BtfError::UnexpectedBtfType { type_id });
}
}
};

return Ok(size as usize);
}

Err(BtfError::MaximumTypeDepthReached {
type_id: root_type_id,
})
}

/// Encodes the metadata as BTF format
pub fn to_bytes(&self) -> Vec<u8> {
// Safety: btf_header is POD
@@ -473,6 +539,38 @@ impl Btf {
buf
}

pub(crate) fn get_extern_data_sec_entry_info(
&self,
target_var_name: &str,
) -> Result<(String, Var), BtfError> {
for t in &self.types.types {
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Perf wise this isn't great, as we iterate all the types for each kconfig symbol.
We should probably do one pass where we find the datasecs, then only scan those?

let BtfType::DataSec(d) = t else {
continue;
};
let sec_name = self.string_at(d.name_offset)?;

for d in &d.entries {
let BtfType::Var(var) = self.types.type_by_id(d.btf_type)? else {
continue;
};

if target_var_name == self.string_at(var.name_offset)? {
if var.linkage == VarLinkage::Extern {
return Ok((sec_name.into(), var.clone()));
} else {
return Err(BtfError::InvalidExternalSymbol {
symbol_name: target_var_name.into(),
});
}
}
}
}

Err(BtfError::ExternalSymbolNotFound {
symbol_name: target_var_name.into(),
})
}

// This follows the same logic as libbpf's bpf_object__sanitize_btf() function.
// https://github.com/libbpf/libbpf/blob/05f94ddbb837f5f4b3161e341eed21be307eaa04/src/libbpf.c#L2701
//
@@ -610,6 +708,14 @@ impl Btf {
}
};
e.offset = *offset as u32;

if var.linkage == VarLinkage::Extern {
let mut var = var.clone();
var.linkage = VarLinkage::Global;

types.types[e.btf_type as usize] = BtfType::Var(var);
}

debug!(
"{} {}: VAR {}: fixup offset {}",
kind, name, var_name, offset
@@ -730,6 +836,107 @@ impl Default for Btf {
}

impl Object {
fn patch_extern_data_internal(
&mut self,
externs: &HashMap<String, Vec<u8>>,
) -> Result<Option<(SectionIndex, Vec<u8>)>, BtfError> {
if let Some(ref mut obj_btf) = &mut self.btf {
if obj_btf.is_empty() {
return Ok(None);
}

let mut kconfig_map_index = 0;
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What is going on here? This is overridden at line 856?


for map in self.maps.values() {
if map.section_index() >= kconfig_map_index {
kconfig_map_index = map.section_index() + 1;
}
}

let kconfig_map_index = self.maps.len();

let symbols = self
.symbol_table
.iter_mut()
.filter(|(_, s)| s.name.is_some() && s.section_index.is_none() && s.is_external)
.map(|(_, s)| (s.name.as_ref().unwrap().clone(), s));

let mut section_data = Vec::<u8>::new();
let mut offset = 0u64;
let mut has_extern_data = false;

for (name, symbol) in symbols {
let (datasec_name, var) = obj_btf.get_extern_data_sec_entry_info(&name)?;

if datasec_name == ".kconfig" {
has_extern_data = true;

let type_size = obj_btf.type_size(var.btf_type)?;
let type_align = obj_btf.type_align(var.btf_type)? as u64;

let mut external_value_opt = externs.get(&name);
let empty_data = vec![0; type_size];

if external_value_opt.is_none() && symbol.is_weak {
external_value_opt = Some(&empty_data);
}

if let Some(data) = external_value_opt {
symbol.address = (offset + (type_align - 1)) & !(type_align - 1);
symbol.size = type_size as u64;
symbol.section_index = Some(kconfig_map_index);

section_data.resize((symbol.address - offset) as usize, 0);

self.symbol_offset_by_name.insert(name, symbol.address);
offset = symbol.address + section_data.len() as u64;
section_data.extend(data);
} else {
return Err(BtfError::ExternalSymbolNotFound { symbol_name: name });
}
}
}

if has_extern_data {
self.section_infos.insert(
".kconfig".into(),
(SectionIndex(kconfig_map_index), section_data.len() as u64),
);

return Ok(Some((SectionIndex(kconfig_map_index), section_data)));
}
}
Ok(None)
}

/// Patches extern data
pub fn patch_extern_data(
&mut self,
externs: &HashMap<String, Vec<u8>>,
) -> Result<(), BtfError> {
if let Some((section_index, data)) = self.patch_extern_data_internal(externs)? {
self.maps.insert(
".kconfig".into(),
Map::Legacy(LegacyMap {
def: bpf_map_def {
map_type: bpf_map_type::BPF_MAP_TYPE_ARRAY as u32,
key_size: mem::size_of::<u32>() as u32,
value_size: data.len() as u32,
max_entries: 1,
map_flags: BPF_F_RDONLY_PROG,
..Default::default()
},
section_index: section_index.0,
section_kind: EbpfSectionKind::Rodata,
symbol_index: None,
data,
}),
);
}

Ok(())
}

/// Fixes up and sanitizes BTF data.
///
/// Mostly, it removes unsupported types and works around LLVM behaviours.
6 changes: 5 additions & 1 deletion aya-obj/src/btf/types.rs
Original file line number Diff line number Diff line change
@@ -1292,11 +1292,15 @@ impl BtfType {
BtfType::Struct(t) => Some(t.size),
BtfType::Union(t) => Some(t.size),
BtfType::DataSec(t) => Some(t.size),
BtfType::Ptr(_) => Some(mem::size_of::<&()>() as u32),
BtfType::Ptr(_) => Some(Self::ptr_size()),
_ => None,
}
}

pub(crate) fn ptr_size() -> u32 {
mem::size_of::<&()>() as u32
}

pub(crate) fn btf_type(&self) -> Option<u32> {
match self {
BtfType::Const(t) => Some(t.btf_type),
13 changes: 13 additions & 0 deletions aya-obj/src/obj.rs
Original file line number Diff line number Diff line change
@@ -49,6 +49,7 @@ pub struct Features {
devmap_prog_id: bool,
prog_info_map_ids: bool,
prog_info_gpl_compatible: bool,
bpf_syscall_wrapper: bool,
btf: Option<BtfFeatures>,
}

@@ -65,6 +66,7 @@ impl Features {
devmap_prog_id: bool,
prog_info_map_ids: bool,
prog_info_gpl_compatible: bool,
bpf_syscall_wrapper: bool,
btf: Option<BtfFeatures>,
) -> Self {
Self {
@@ -77,6 +79,7 @@ impl Features {
devmap_prog_id,
prog_info_map_ids,
prog_info_gpl_compatible,
bpf_syscall_wrapper,
btf,
}
}
@@ -118,6 +121,10 @@ impl Features {
pub fn devmap_prog_id(&self) -> bool {
self.devmap_prog_id
}
/// Returns whether BPF syscall wrapper hooking is supported.
pub fn bpf_syscall_wrapper(&self) -> bool {
self.bpf_syscall_wrapper
}

/// Returns whether `bpf_prog_info` supports `nr_map_ids` & `map_ids` fields.
pub fn prog_info_map_ids(&self) -> bool {
@@ -483,6 +490,8 @@ impl Object {
address: symbol.address(),
size: symbol.size(),
is_definition: symbol.is_definition(),
is_external: symbol.is_undefined() && (symbol.is_global() || symbol.is_weak()),
is_weak: symbol.is_weak(),
kind: symbol.kind(),
};
bpf_obj.symbol_table.insert(symbol.index().0, sym);
@@ -1465,6 +1474,8 @@ mod tests {
size,
is_definition: false,
kind: SymbolKind::Text,
is_external: false,
is_weak: false,
},
);
obj.symbols_by_section
@@ -2601,6 +2612,8 @@ mod tests {
address: 0,
size: 3,
is_definition: true,
is_external: false,
is_weak: false,
kind: SymbolKind::Data,
},
);
17 changes: 12 additions & 5 deletions aya-obj/src/relocation.rs
Original file line number Diff line number Diff line change
@@ -99,6 +99,8 @@ pub(crate) struct Symbol {
pub(crate) address: u64,
pub(crate) size: u64,
pub(crate) is_definition: bool,
pub(crate) is_external: bool,
pub(crate) is_weak: bool,
pub(crate) kind: SymbolKind,
}

@@ -218,7 +220,9 @@ fn relocate_maps<'a, I: Iterator<Item = &'a Relocation>>(
};

// calls and relocation to .text symbols are handled in a separate step
if insn_is_call(&instructions[ins_index]) || text_sections.contains(&section_index) {
if insn_is_call(&instructions[ins_index])
|| (text_sections.contains(&section_index) && !sym.is_external)
{
continue;
}

@@ -367,10 +371,11 @@ impl<'a> FunctionLinker<'a> {
// only consider text relocations, data relocations are
// relocated in relocate_maps()
sym.kind == SymbolKind::Text
|| sym
.section_index
.map(|section_index| self.text_sections.contains(&section_index))
.unwrap_or(false)
|| (!sym.is_external
&& sym
.section_index
.map(|section_index| self.text_sections.contains(&section_index))
.unwrap_or(false))
});

// not a call and not a text relocation, we don't need to do anything
@@ -510,6 +515,8 @@ mod test {
address,
size,
is_definition: false,
is_external: false,
is_weak: false,
kind: SymbolKind::Data,
}
}
1 change: 1 addition & 0 deletions aya/Cargo.toml
Original file line number Diff line number Diff line change
@@ -24,6 +24,7 @@ log = { workspace = true }
object = { workspace = true, features = ["elf", "read_core", "std", "write"] }
thiserror = { workspace = true }
tokio = { workspace = true, features = ["rt"], optional = true }
flate2 = "1.0"

[dev-dependencies]
tempfile = { workspace = true }
147 changes: 139 additions & 8 deletions aya/src/bpf.rs
Original file line number Diff line number Diff line change
@@ -1,7 +1,8 @@
use std::{
borrow::Cow,
collections::{HashMap, HashSet},
fs, io,
fs::{self, File},
io::{self, Read},
os::{
fd::{AsFd as _, AsRawFd as _},
raw::c_int,
@@ -16,6 +17,8 @@ use aya_obj::{
relocation::EbpfRelocationError,
EbpfSectionKind, Features,
};
use flate2::read::GzDecoder;
use lazy_static::lazy_static;
use log::{debug, warn};
use thiserror::Error;

@@ -36,14 +39,15 @@ use crate::{
SkMsg, SkSkb, SkSkbKind, SockOps, SocketFilter, TracePoint, UProbe, Xdp,
},
sys::{
bpf_load_btf, is_bpf_cookie_supported, is_bpf_global_data_supported,
is_btf_datasec_supported, is_btf_decl_tag_supported, is_btf_enum64_supported,
is_btf_float_supported, is_btf_func_global_supported, is_btf_func_supported,
is_btf_supported, is_btf_type_tag_supported, is_info_gpl_compatible_supported,
is_info_map_ids_supported, is_perf_link_supported, is_probe_read_kernel_supported,
is_prog_id_supported, is_prog_name_supported, retry_with_verifier_logs,
self, bpf_load_btf, is_bpf_cookie_supported, is_bpf_global_data_supported,
is_bpf_syscall_wrapper_supported, is_btf_datasec_supported, is_btf_decl_tag_supported,
is_btf_enum64_supported, is_btf_float_supported, is_btf_func_global_supported,
is_btf_func_supported, is_btf_supported, is_btf_type_tag_supported,
is_info_gpl_compatible_supported, is_info_map_ids_supported, is_perf_link_supported,
is_probe_read_kernel_supported, is_prog_id_supported, is_prog_name_supported,
retry_with_verifier_logs,
},
util::{bytes_of, bytes_of_slice, page_size, possible_cpus, POSSIBLE_CPUS},
util::{bytes_of, bytes_of_slice, page_size, possible_cpus, KernelVersion, POSSIBLE_CPUS},
};

pub(crate) const BPF_OBJ_NAME_LEN: usize = 16;
@@ -98,6 +102,7 @@ fn detect_features() -> Features {
is_prog_id_supported(BPF_MAP_TYPE_DEVMAP),
is_info_map_ids_supported(),
is_info_gpl_compatible_supported(),
is_bpf_syscall_wrapper_supported(),
btf,
);
debug!("BPF Feature Detection: {:#?}", f);
@@ -109,6 +114,131 @@ pub fn features() -> &'static Features {
&FEATURES
}

lazy_static! {
static ref KCONFIG_DEFINITION: HashMap<String, Vec<u8>> = compute_kconfig_definition(&FEATURES);
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Instead of this lazy static, we could have a KConfig type. Then we could have
EbpfLoader::with_kconfig(kconfig). This way we don't force people who don't
use kconfig to take the extra memory hit. It's a small hit, but people are using
aya in embedded systems so we shouldn't increase mem usage if we can.

}

fn compute_kconfig_definition(features: &Features) -> HashMap<String, Vec<u8>> {
let mut result = HashMap::new();

if let Ok(KernelVersion {
major,
minor,
patch,
}) = KernelVersion::current()
{
result.insert(
"LINUX_KERNEL_VERSION".to_string(),
{
let value = (u64::from(major) << 16) + (u64::from(minor) << 8) + u64::from(patch);
value.to_ne_bytes()
}
.to_vec(),
);
}

let bpf_cookie = if features.bpf_cookie() { 1u64 } else { 0u64 };
let bpf_syscall_wrapper = if features.bpf_syscall_wrapper() {
1u64
} else {
0u64
};

result.insert(
"LINUX_HAS_BPF_COOKIE".to_string(),
bpf_cookie.to_ne_bytes().to_vec(),
);

result.insert(
"LINUX_HAS_SYSCALL_WRAPPER".to_string(),
bpf_syscall_wrapper.to_ne_bytes().to_vec(),
);

if let Some(raw_config) = read_kconfig() {
for line in raw_config.lines() {
if !line.starts_with("CONFIG_") {
continue;
}

let mut parts = line.split('=');
let (key, raw_value) = match (parts.next(), parts.next(), parts.count()) {
(Some(key), Some(value), 0) => (key, value),
_ => continue,
};

let value = match raw_value.chars().next() {
Some('n') => 0_u64.to_ne_bytes().to_vec(),
Some('y') => 1_u64.to_ne_bytes().to_vec(),
Some('m') => 2_u64.to_ne_bytes().to_vec(),
Some('"') => {
if raw_value.len() < 2 || !raw_value.ends_with('"') {
continue;
}

let raw_value = &raw_value[1..raw_value.len() - 1];
raw_value.as_bytes().to_vec()
}
Some(_) => {
if let Ok(value) = raw_value.parse::<u64>() {
value.to_ne_bytes().to_vec()
} else {
continue;
}
}
None => continue,
};

result.insert(key.to_string(), value);
}
}

result
}

fn read_kconfig() -> Option<String> {
let config_path = PathBuf::from("/proc/config.gz");
if config_path.exists() {
debug!("Found kernel config at {}", config_path.to_string_lossy());
return read_kconfig_file(&config_path, true);
}

let Ok(release) = sys::kernel_release() else {
return None;
};

let config_path = PathBuf::from("/boot").join(format!("config-{}", release));
if config_path.exists() {
debug!("Found kernel config at {}", config_path.to_string_lossy());
return read_kconfig_file(&config_path, false);
}

None
}

fn read_kconfig_file(path: &PathBuf, gzip: bool) -> Option<String> {
let mut output = String::new();

let res = if gzip {
File::open(path)
.map(GzDecoder::new)
.and_then(|mut file| file.read_to_string(&mut output))
} else {
File::open(path).and_then(|mut file| file.read_to_string(&mut output))
};

match res {
Ok(_) => Some(output),
Err(e) => {
warn!(
"Unable to read kernel config {}: {:?}",
path.to_string_lossy(),
e
);
None
}
}
}

/// Builder style API for advanced loading of eBPF programs.
///
/// Loading eBPF code involves a few steps, including loading maps and applying
@@ -399,6 +529,7 @@ impl<'a> EbpfLoader<'a> {
} = self;
let mut obj = Object::parse(data)?;
obj.patch_map_data(globals.clone())?;
obj.patch_extern_data(&KCONFIG_DEFINITION)?;

let btf_fd = if let Some(features) = &FEATURES.btf() {
if let Some(btf) = obj.fixup_and_sanitize_btf(features)? {
2 changes: 1 addition & 1 deletion aya/src/programs/mod.rs
Original file line number Diff line number Diff line change
@@ -38,7 +38,7 @@
// modules we don't export
mod info;
mod probe;
pub(crate) mod probe;
mod utils;

// modules we explicitly export so their pub items (Links etc) get exported too
2 changes: 1 addition & 1 deletion aya/src/programs/probe.rs
Original file line number Diff line number Diff line change
@@ -145,7 +145,7 @@ pub(crate) fn detach_debug_fs(event: ProbeEvent) -> Result<(), ProgramError> {
})
}

fn create_as_probe(
pub(crate) fn create_as_probe(
kind: ProbeKind,
fn_name: &OsStr,
offset: u64,
40 changes: 39 additions & 1 deletion aya/src/sys/bpf.rs
Original file line number Diff line number Diff line change
@@ -1,6 +1,6 @@
use std::{
cmp,
ffi::{c_char, CStr, CString},
ffi::{c_char, CStr, CString, OsStr},
io, iter,
mem::{self, MaybeUninit},
os::fd::{AsFd as _, AsRawFd as _, BorrowedFd, FromRawFd as _, RawFd},
@@ -30,6 +30,7 @@ use crate::{
},
copy_instructions,
},
programs::probe::create_as_probe,
sys::{syscall, SysResult, Syscall, SyscallError},
util::KernelVersion,
Btf, Pod, VerifierLogLevel, BPF_OBJ_NAME_LEN, FEATURES,
@@ -950,6 +951,43 @@ pub(crate) fn is_prog_id_supported(map_type: bpf_map_type) -> bool {
fd.is_ok()
}

fn arch_specific_syscall_prefix() -> Option<&'static str> {
if cfg!(target_arch = "aarch64") {
Some("arm64")
} else if cfg!(target_arch = "arm") {
Some("arm")
} else if cfg!(target_arch = "powerpc") {
Some("powerpc")
} else if cfg!(target_arch = "powerpc64") {
Some("powerpc64")
} else if cfg!(target_arch = "riscv32") || cfg!(target_arch = "riscv64") {
Some("riscv")
} else if cfg!(target_arch = "x86") {
Some("ia32")
} else if cfg!(target_arch = "x86_64") {
Some("x64")
} else if cfg!(target_arch = "s390x") {
Some("s390x")
} else if cfg!(target_arch = "mips") || cfg!(target_arch = "mips64") {
Some("mips")
} else {
None
}
}

pub(crate) fn is_bpf_syscall_wrapper_supported() -> bool {
let syscall_prefix_opt = arch_specific_syscall_prefix();

if let Some(syscall_prefix) = syscall_prefix_opt {
let syscall_name = format!("__{}_sys_bpf", syscall_prefix);
let syscall_name = OsStr::new(syscall_name.as_str());

return create_as_probe(crate::programs::ProbeKind::KProbe, syscall_name, 0, None).is_ok();
}

false
}

pub(crate) fn is_btf_supported() -> bool {
let mut btf = Btf::new();
let name_offset = btf.add_string("int");
23 changes: 23 additions & 0 deletions aya/src/sys/mod.rs
Original file line number Diff line number Diff line change
@@ -191,3 +191,26 @@ impl From<Stats> for crate::generated::bpf_stats_type {
pub fn enable_stats(stats_type: Stats) -> Result<OwnedFd, SyscallError> {
bpf_enable_stats(stats_type.into()).map(|fd| fd.into_inner())
}

#[cfg(test)]
pub(crate) fn kernel_release() -> Result<String, ()> {
Ok("unknown".to_string())
}

#[cfg(not(test))]
pub(crate) fn kernel_release() -> Result<String, ()> {
use std::ffi::CStr;

use libc::utsname;

unsafe {
let mut v = mem::zeroed::<utsname>();
if libc::uname(&mut v as *mut _) != 0 {
return Err(());
}

let release = CStr::from_ptr(v.release.as_ptr());

Ok(release.to_string_lossy().into_owned())
}
}
38 changes: 38 additions & 0 deletions test/integration-test/bpf/kconfig.bpf.c
Original file line number Diff line number Diff line change
@@ -0,0 +1,38 @@
// clang-format off
#include <vmlinux.h>
#include <bpf/bpf_helpers.h>
// clang-format on

// CONFIG_BPF=y => 1
extern unsigned int CONFIG_BPF __kconfig;
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We should test char, short, int and long here, to test different alignments

// CONFIG_PANIC_TIMEOUT=0 => 0
extern unsigned int CONFIG_PANIC_TIMEOUT __kconfig;
// CONFIG_DEFAULT_HUNG_TASK_TIMEOUT=120
extern unsigned int CONFIG_DEFAULT_HUNG_TASK_TIMEOUT __kconfig;
// CONFIG_DEFAULT_HOSTNAME
extern char CONFIG_DEFAULT_HOSTNAME[] __kconfig;

SEC("xdp")
int kconfig(struct xdp_md *ctx) {
if (CONFIG_BPF != 1) {
return XDP_DROP;
}

if (CONFIG_PANIC_TIMEOUT != 0) {
return XDP_DROP;
}

if (CONFIG_DEFAULT_HUNG_TASK_TIMEOUT != 120) {
return XDP_DROP;
}

for (int i = 0; i < 7; i++) {
if ("(none)"[i] != CONFIG_DEFAULT_HOSTNAME[i]) {
return XDP_DROP;
}
}

return XDP_PASS;
}

char _license[] SEC("license") = "GPL";
1 change: 1 addition & 0 deletions test/integration-test/build.rs
Original file line number Diff line number Diff line change
@@ -71,6 +71,7 @@ fn main() {
("multimap-btf.bpf.c", false),
("reloc.bpf.c", true),
("text_64_64_reloc.c", false),
("kconfig.bpf.c", false),
];

if build_integration_bpf {
1 change: 1 addition & 0 deletions test/integration-test/src/lib.rs
Original file line number Diff line number Diff line change
@@ -9,6 +9,7 @@ pub const RELOC_BTF: &[u8] =
include_bytes_aligned!(concat!(env!("OUT_DIR"), "/reloc.bpf.target.o"));
pub const TEXT_64_64_RELOC: &[u8] =
include_bytes_aligned!(concat!(env!("OUT_DIR"), "/text_64_64_reloc.o"));
pub const KCONFIG: &[u8] = include_bytes_aligned!(concat!(env!("OUT_DIR"), "/kconfig.bpf.o"));

pub const LOG: &[u8] = include_bytes_aligned!(concat!(env!("OUT_DIR"), "/log"));
pub const MAP_TEST: &[u8] = include_bytes_aligned!(concat!(env!("OUT_DIR"), "/map_test"));
13 changes: 13 additions & 0 deletions test/integration-test/src/tests/smoke.rs
Original file line number Diff line number Diff line change
@@ -69,3 +69,16 @@ fn extension() {
.load(pass.fd().unwrap().try_clone().unwrap(), "xdp_pass")
.unwrap();
}

#[test]
fn kconfig() {
let kernel_version = KernelVersion::current().unwrap();
if kernel_version < KernelVersion::new(5, 9, 0) {
eprintln!("skipping test on kernel {kernel_version:?}, XDP uses netlink");
return;
}
let mut bpf = Ebpf::load(crate::KCONFIG).unwrap();
let pass: &mut Xdp = bpf.program_mut("kconfig").unwrap().try_into().unwrap();
pass.load().unwrap();
pass.attach("lo", XdpFlags::default()).unwrap();
}
8 changes: 8 additions & 0 deletions xtask/public-api/aya-obj.txt
Original file line number Diff line number Diff line change
@@ -1,10 +1,14 @@
pub mod aya_obj
pub mod aya_obj::btf
pub enum aya_obj::btf::BtfError
pub aya_obj::btf::BtfError::ExternalSymbolNotFound
pub aya_obj::btf::BtfError::ExternalSymbolNotFound::symbol_name: alloc::string::String
pub aya_obj::btf::BtfError::FileError
pub aya_obj::btf::BtfError::FileError::error: std::io::error::Error
pub aya_obj::btf::BtfError::FileError::path: std::path::PathBuf
pub aya_obj::btf::BtfError::InvalidDatasec
pub aya_obj::btf::BtfError::InvalidExternalSymbol
pub aya_obj::btf::BtfError::InvalidExternalSymbol::symbol_name: alloc::string::String
pub aya_obj::btf::BtfError::InvalidHeader
pub aya_obj::btf::BtfError::InvalidInfo
pub aya_obj::btf::BtfError::InvalidInfo::len: usize
@@ -7106,6 +7110,7 @@ pub fn aya_obj::Features::bpf_global_data(&self) -> bool
pub fn aya_obj::Features::bpf_name(&self) -> bool
pub fn aya_obj::Features::bpf_perf_link(&self) -> bool
pub fn aya_obj::Features::bpf_probe_read_kernel(&self) -> bool
pub fn aya_obj::Features::bpf_syscall_wrapper(&self) -> bool
pub fn aya_obj::Features::btf(&self) -> core::option::Option<&aya_obj::btf::BtfFeatures>
pub fn aya_obj::Features::cpumap_prog_id(&self) -> bool
pub fn aya_obj::Features::devmap_prog_id(&self) -> bool
@@ -7214,6 +7219,7 @@ pub aya_obj::obj::Object::maps: std::collections::hash::map::HashMap<alloc::stri
pub aya_obj::obj::Object::programs: std::collections::hash::map::HashMap<alloc::string::String, aya_obj::Program>
impl aya_obj::Object
pub fn aya_obj::Object::fixup_and_sanitize_btf(&mut self, features: &aya_obj::btf::BtfFeatures) -> core::result::Result<core::option::Option<&aya_obj::btf::Btf>, aya_obj::btf::BtfError>
pub fn aya_obj::Object::patch_extern_data(&mut self, externs: &std::collections::hash::map::HashMap<alloc::string::String, alloc::vec::Vec<u8>>) -> core::result::Result<(), aya_obj::btf::BtfError>
impl aya_obj::Object
pub fn aya_obj::Object::parse(data: &[u8]) -> core::result::Result<aya_obj::Object, aya_obj::ParseError>
pub fn aya_obj::Object::patch_map_data(&mut self, globals: std::collections::hash::map::HashMap<&str, (&[u8], bool)>) -> core::result::Result<(), aya_obj::ParseError>
@@ -7966,6 +7972,7 @@ pub fn aya_obj::Features::bpf_global_data(&self) -> bool
pub fn aya_obj::Features::bpf_name(&self) -> bool
pub fn aya_obj::Features::bpf_perf_link(&self) -> bool
pub fn aya_obj::Features::bpf_probe_read_kernel(&self) -> bool
pub fn aya_obj::Features::bpf_syscall_wrapper(&self) -> bool
pub fn aya_obj::Features::btf(&self) -> core::option::Option<&aya_obj::btf::BtfFeatures>
pub fn aya_obj::Features::cpumap_prog_id(&self) -> bool
pub fn aya_obj::Features::devmap_prog_id(&self) -> bool
@@ -8074,6 +8081,7 @@ pub aya_obj::Object::maps: std::collections::hash::map::HashMap<alloc::string::S
pub aya_obj::Object::programs: std::collections::hash::map::HashMap<alloc::string::String, aya_obj::Program>
impl aya_obj::Object
pub fn aya_obj::Object::fixup_and_sanitize_btf(&mut self, features: &aya_obj::btf::BtfFeatures) -> core::result::Result<core::option::Option<&aya_obj::btf::Btf>, aya_obj::btf::BtfError>
pub fn aya_obj::Object::patch_extern_data(&mut self, externs: &std::collections::hash::map::HashMap<alloc::string::String, alloc::vec::Vec<u8>>) -> core::result::Result<(), aya_obj::btf::BtfError>
impl aya_obj::Object
pub fn aya_obj::Object::parse(data: &[u8]) -> core::result::Result<aya_obj::Object, aya_obj::ParseError>
pub fn aya_obj::Object::patch_map_data(&mut self, globals: std::collections::hash::map::HashMap<&str, (&[u8], bool)>) -> core::result::Result<(), aya_obj::ParseError>
22 changes: 22 additions & 0 deletions xtask/src/run.rs
Original file line number Diff line number Diff line change
@@ -340,6 +340,28 @@ pub fn run(opts: Options) -> Result<()> {
}
}
}

// Copy kernel configs as well (based on Debian path conventions)
let config_path = PathBuf::from(
kernel_image
.to_string_lossy()
.replace("vmlinuz-", "config-"),
);
if config_path.exists() {
let mut destination = PathBuf::from("/boot");
destination.push(config_path.file_name().expect("filename"));
for bytes in [
"dir /boot 0755 0 0\n".as_bytes(),
"file ".as_bytes(),
destination.as_os_str().as_bytes(),
" ".as_bytes(),
config_path.as_os_str().as_bytes(),
" 0755 0 0\n".as_bytes(),
] {
stdin.write_all(bytes).expect("write");
}
}

// Must explicitly close to signal EOF.
drop(stdin);